Ultherapy uses ultrasound targeting the 4.5 mm SMAS layer deep under your skin,...

https://blogfreely.net/sordusgvrj/i-want-faster-results-should-i-combine-threads-and-ultherapy

Ultherapy uses ultrasound targeting the 4.5 mm SMAS layer deep under your skin, which is tough for RF or standard HIFU to reach. This makes it great for lifting over 3 to 6 months as your collagen rebuilds